Strawberry tongue, or raspberry tongue, is glossitis which manifests with hyperplastic (enlarged) fungiform papillae, giving the appearance of a strawberry. White strawberry tongue is where there is a white coating on the tongue through which the hyperplastic fungiform papillae protrude.

Red strawberry tongue is where the white coating is lost and a dark red, erythematous surface is revealed, interspaced with the hyperplastic fungiform papillae. White strawberry tongue is seen in early scarlet fever (a systemic infection of group A β- hemolytic streptococci), and red strawberry tongue occurs later, after 4–5 days.

Strawberry tongue is also seen in Kawasaki disease (a vasculitic disorder primarily occurring in children under 5), and toxic shock syndrome. It may mimic other types of glossitis or Vitamin B12 deficiency.

More Info: en.wikipedia.org